Tendonitis is a generalized term for aggravation and irritation of the tendons, which connect muscle to bone. Tendonitis is common in athletes with repeated activities involved in their sports, including running, overhead hitting, and throwing, resulting in mild to severe inflammation of the tendons. Symptoms of tendonitis include swelling and pain at the site of the tendon, as well as a thickening of the tendon. These symptoms can be aggravated by lack of stretching and conditioning, as well as poor nutrition, and improper equipment. To combat this persistent pain, choose Cornerstone for honest, accurate advice and unrivaled sports medicine treatment.